Showing papers by "University of Malaya published in 1981"
TL;DR: The closed-field magnetic retention system described avoids any possibility of magnetic field effects on tissues by using paired magnets and a fixed and detachable keeper in a modified horseshoe arrangement.
Abstract: Magnets have been used as aids to denture retention for many years with some success. The development of new cobalt and rare earth magnet alloys has greatly extended the potential application of magnetic retention in removable partial dentures, complete overdentures, fixed partial dentures, and sectional dentures. Effects of magnetic fields on tissues have been investigated extensively, with conflicting results, but reports describing dental applications for magnets claim no damaging tissue effects. The closed-field magnetic retention system described avoids any possibility of magnetic field effects on tissues by using paired magnets and a fixed and detachable keeper in a modified horseshoe arrangement. The detachable keeper is cemented or screwed to a decoronated, root-treated tooth. The denture-retention element, consisting of paired magnets and a fixed keeper, abuts the keeper in the tooth root and holds the denture in place by magnetic attraction. When in position, there is no external field surrounding the denture or tooth root. This arrangement also doubles the available retention. The shape, size, and configuration of the two magnets and fixed and removable keepers were chosen to provide maximum retention in a magnetic denture retention unit of a size convenient for most applications. The retention provided is approximately 300 gm per unit. The magnet alloy, Co 5 Sm, is very hard but brittle, and it can corrode in the mouth. To prevent this from occurring in service, end plates protect the exposed magnet faces. The plates, of the same stainless steel alloy as the keepers, prevent magnet corrosion and reduce wear at the denture-retention keeper-element interface in service.
97 citations
TL;DR: In this paper, a technique for the analysis of the insoluble rubber is described, which is made possible by using the methyl deformation band at 1380 cm −1 as internal standard.
80 citations
TL;DR: Findings indicate that margosa oil may be involved in the aetiology of Reye's syndrome among Indians in Malaysia.
64 citations
TL;DR: The heuristic algorithm of this paper improves on feasible solutions by exchanging capacities between pairs of regions by imbeding an optimization procedure to seek the best feasible solution in the direction specified by the heuristic.
Abstract: Consider the problem of determining a schedule of capacity expansions for m producing regions and a schedule of shipments from the regions to n markets so as to meet the market demands over a T-period planning horizon at minimum discounted capacity expansion and shipment costs. Both of these costs are assumed to be proportional to the amounts involved. The heuristic algorithm of this paper improves on feasible solutions by exchanging capacities between pairs of regions. The algorithm imbeds an optimization procedure to seek the best feasible solution in the direction specified by the heuristic. Computational results for both real and randomly generated problems show that the heuristic algorithm is computationally efficient and yields close to optimum solutions.
61 citations
TL;DR: In this paper, the authors presented microwave measurements of tropical vegetation samples (grass, casuarina, rubber leaf, rubber wood) as a function of moisture content at 21°C were presented.
Abstract: Microwave measurements of tropical vegetation samples (grass, casuarina, rubber leaf, rubber wood) at 9.5 GHz as a function of moisture content at 21°C are presented. A comparison is made with results calculated from six models for the permittivity of dielectric mixtures. Of these, only one of the models due to Polder, van Santen, and deLoor is found to give reasonable agreement, particularly for the real part of the permittivity. It is clear that more complex formulations for the permittivity of vegetation are necessary to model its behaviour as a function of moisture content and frequency.
44 citations
TL;DR: It is found that in areas of natural settlement Thais carinifera may represent a potentially more important energy flow pathway than Natica maculosa but because of the differences in the preferred size of prey N.maculosa probably has a greater influence on the final yield of the prey population.
43 citations
TL;DR: It is suggested that pH changes produced by rhizobia growing on yeast-extract mannitol media are caused by the preferential utilization of sugars by fast-growing organisms and nitrogenous compounds by slow-growing ones.
Abstract: Three fast-growing rhizobia ( Rhizobium meliloti isolated from Medicago saliva, R. trifolii from Trifolium subterraneum , and Rhizohium sp. from Leucaena leucocephala ) and three slow-growing rhizobia R. japonicum from Glycine max, Rhizobium spp from Centrosema pubescens and Crotolaria anagyroides ) were grown in defined media. The mean generation times of the fast-growing and slowgrowing strains were 3.8 h and 8.6 h respectively. Slow-growing organisms raised the initial pH of the defined medium while the fast-growing organisms lowered it. Rates of oxygen consumption tended to be higher in the slow-growing organisms. UMKL 19 (isolated from L. leucocephala ) possessed all the normal reactions of fast-growing rhizobia but had a single sub-polar flagellum, similar to the three slow-growing strains studied. Certain combinations of amino acids and sugars (e.g. glutamine and galactose) induced an acidic reaction in the fast-growing organisms while the slow-growing ones changed the media to alkaline. Fast-growing organisms utilized more galactose for growth compared to slow-growing ones. Both types of organisms synthesized and released a wide range of amino acids into the medium. We suggest that pH changes produced by rhizobia growing on yeast-extract mannitol media are caused by the preferential utilization of sugars by fast-growing organisms and nitrogenous compounds by slow-growing ones.
36 citations
TL;DR: The partial mole is likely to be part of a spectrum of gestational trophoblastic disease and should be viewed as a potentially malignant lesion.
Abstract: Summary: Recent studies suggest that partial hydatidiform moles are not potentially malignant and that prophylactic chemotherapy need not be administered. Our experience does not support that opinion. We report a 28-year-old Malay primigravida who succumbed to choriocarcinoma complicating a partial mole. The partial mole is likely to be part of a spectrum of gestational trophoblastic disease and should be viewed as a potentially malignant lesion.
31 citations
TL;DR: The Malay cases of amok, latah and possession hysteria are discussed as instances of anti-structural behaviors that dramatize role-reversals and role-enhancement.
Abstract: Turner's concepts of structure and anti-structure are applied to the culture-bound syndromes to demonstrate that they are dialectical aspects of cultural reality. The Malay cases of amok, latah and possession hysteria are discussed as instances of anti-structural behaviors that dramatize role-reversals and role-enhancement. The performers of these behaviors are not subjected to the Malay code of moral conduct. The supernatural ethos in Malay culture plays an important role in shaping tolerance towards them. Although this tolerance has been gradually eroded as a result of the introduction of Western psychiatry, the anti-structural status of these syndromes has not faded away but has assumed new meanings in terms of psychopathology.
30 citations
TL;DR: In this study among children with acute lymphoblastic leukemia, more febrile episodes occurred during induction of remission and relapse than during remission, and evidence suggests that the underlying malignancy is the more likely cause of fever if the neutrophil count exceeds 200 per mm3.
Abstract: In this study among children with acute lymphoblastic leukemia, more febrile episodes occurred during induction of remission and relapse than during remission. Infection was mainly responsible for fever during remission, regardless of the neutrophil count. However, during induction and relapse, evidence suggests that the underlying malignancy is the more likely cause of fever if the neutrophil count exceeds 200 per mm3. For all cases, the risk of serious infection was high with severe neutropenia (neutrophil count less than 200 per mm3). Of the organisms identified, gram-positive and gram-negative bacteria were equally represented. Infection remains a serious problem in the management of children with leukemia.
30 citations
TL;DR: In this article, structural features of the isolated complexes both in the solid state and in solution are discussed based on spectral (IR, UV, NMR, Mossbauer) evidence.
TL;DR: Choice between males with or without display sites, on gross plumage and display differences, provides an alternative explanation for the evolution of the males' plumage.
Abstract: A study of the Great Argus pheasant Argusianus argus is described. Cleared display sites are owned each by a single male which calls to attract females, while other adult and subadult males maintain no such sites. Evidence is presented to show that vocal differences between males at display sites are slight and unstable, and are therefore unlikely to be used by females in mate choice. No evidence was obtained to suggest that females wander from display site to site and mate with the best male chosen by visual comparison of subtle plumage variation, although the classical assumption has been that such choice accounts for the evolution of the males' extravagant plumage. Females may by chance meet males without display sites at random in the forest, but the displays of such males are probably insufficiently stimulating to induce the female to copulate. Choice between males with or without display sites, on gross plumage and display differences, provides an alternative explanation for the evolution of the males' plumage.
TL;DR: Differences in the utilization of lipid and protein under conditions of starvation between adult Oxya and adult locusts may be attributed to the migratory habit of the latter.
TL;DR: In this paper, a necessary and sufficient condition for a graph H to be the clique graph of some graph G without multicliqual edges was given, and it was shown that there are infinitely many self-clique graphs having more than one critical generator.
Abstract: An edge which belongs to more than one clique of a given graph is called a multicliqual edge. We find a necessary and sufficient condition for a graph H to be the clique graph of some graph G without multicliqual edges. We also give a characterization of graphs without multicliqual edges that have a unique critical generator. Finally, it is shown that there are infinitely many self-clique graphs having more than one critical generator.
TL;DR: The main factor limiting growth and acetylene reduction activity (ARA) of the A. pinnata-Anabaena assollae symbiotic association on floodwater was phosphorus and full sunlight reduced the growth and ARA of Azolla, and P modified the response ofAzolla to light.
Abstract: SUMMARY
Azolla pinnata grown in a standard medium and on floodwater under the high light (30 to 120 klx) and high temperature (26 to 35°C) conditions of Malaysia doubled its fresh wt in about 3 and 5 days respectively. The main factor limiting growth and acetylene reduction activity (ARA) of the A. pinnata-Anabaena assollae symbiotic association on floodwater was phosphorus. Addition of phosphorus (P) to P-deficient Azolla in floodwater resulted in an immediate increase in ARA followed by an increase in the growth rate. Minus P treatment caused a 50% reduction of ARA but had little effect on the growth rate of Azolla in the first week. Continued culture of Azolla in the minus P medium caused a significant reduction in growth rate, ARA, and the formation of anthocyanin pigment in the fern. Subsequent transfer into a standard medium did not restore its ARA. Full sunlight also reduced the growth and ARA of Azolla, and P modified the response of Azolla to light.
TL;DR: The neurons of origin of the right vagus and its components in both the monkey and albino rats were localized by the retrograde transport of horseradish peroxidase applied to the stomach wall, the vagal trunk and its recurrent laryngeal branch by a combination of operative procedures.
Abstract: The neurons of origin of the right vagus and its components in both the monkey (Macaca fascicularis) and albino rats were localized by the retrograde transport of horseradish peroxidase (HRP) applied to the stomach wall, the vagal trunk and its recurrent laryngeal branch. An attempt was also made to localize the neurons forming the superior laryngeal nerve and those supplying the thoracic organs by a combination of operative procedures. The results showed that the stomach was innervated by neurons distributed throughout the entire rostrocaudal extent of the dorsal motor nucleus (DMN) on both sides of the brain stem. Neurons scattered throughout the entire extent of the DMN and nucleus ambiguus (NA) supplied the thoracic viscera. There did not appear to be any topographic arrangement in the DMN neurons supplying the abdominal and thoracic viscera as reported by other workers, and there was no clear evidence of crossing of vagal fibers in the monkey brain stem, though such crossing was seen in the rat brain stem. Both the superior and inferior ganglia of the vagus nerve were labeled following application of HRP to the vagal trunk. Neurons in the caudal part of the NA gave rise to fibers in the ipsilateral recurrent laryngeal nerve, at least on the right side. The neurons giving rise to the superior laryngeal nerve could not be delineated in this study. In all the experimental procedures described, the hypoglossal nucleus was labeled only after applying HRP to the hypoglossal nerve.
TL;DR: The defense secretion of the nasute termiteBulbitermes singaporensis consists of 1 new and 2 known tetracyclic diterpenes that supports the kinship of the oriental ‘constricted-head’ genera withNasutitermes species in the Philippines and in East Africa.
Abstract: The defense secretion of the nasute termiteBulbitermes singaporensis consists of 1 new and 2 known tetracyclic diterpenes, spectrometrically identified as 14α-acetoxy-6,8-kempadien-3-one, 3α, 14α- and 3β, 14α-diacetoxy-6,8-kempadiene. The presence of these compounds supports the kinship of the oriental ‘constricted-head’ genera withNasutitermes species in the Philippines and in East Africa.
TL;DR: Malaysia has a large variety of traditional medical systems that are a direct reflection of the wide ethnic diversity of its population as mentioned in this paper, which can be grouped into four basic varieties, namely, traditional “native”, traditional Chinese, traditional Indian, and modern medicine, examples of which are described.
Abstract: Malaysia has a large variety of traditional medical systems that are a direct reflection of the wide ethnic diversity of its population. These can be grouped into four basic varieties, namely, traditional “native”, traditional Chinese, traditional Indian, and modern medicine, examples of which are described. In spite of the great inroads made by modern medicine, the traditional systems are firmly established. Patients move from one system to another or use several systems simultaneously. The integration of the traditional Malay birth attendant into the health team is described. The forces influencing the development, acceptance, and integration of the medical systems are discussed.
TL;DR: In this paper, the anodic current overpotential behavior of various pure gases at 1 atm and 700-850°C was investigated in a fuel cell system using an 8 mol% Sc 2 O 3 -stabilized ZrO 2 disc electrolyte.
TL;DR: Serum immunoglobulins, complements C3 and C4 and factor B were assayed in the sera of children with B‐thalassaemia major, siblings and matched controls in an attempt to resolve the controversy surrounding the conflicting results reported in the literature.
Abstract: Serum immunoglobulins, complements C3 and C4 and factor B were assayed in the sera of children with B-thalassaemia major, siblings and matched controls in an attempt to resolve the controversy surrounding the conflicting results reported in the literature. Significantly elevated IgG and decreased C3 and factor B levels were observed in thalassaemic patients who also had a high incidence of HBS hepatitis and other infections. The controversial results probably reflect differences in the incidence of infection, and the presence of circulating immune complexes due to blood transfusions, in the various communities. The alterations in immunoglobulin and complement levels represent a secondary rather than a primary immune disorder.
TL;DR: Following injection of horseradish peroxidase (HRP) solution in the gastrocnemius muscle or the extensor digitorum longus muscle in neonatal and developing albino rats, some neurones in the cervical enlargement, mid-thoracic region and sacral region were labelled.
TL;DR: In this paper, a model of communication is used to show how information about possession is exchanged through reciprocal role behaviors at the primary level and through interpretive accounts at the secondary level.
Abstract: This study is concerned with how diverse definitions of spirit possession events in a factory are organized into predictable equivalence structures. A model of communication is utilized to show how information about possession is exchanged through reciprocal role behaviors at the primary level and through interpretive accounts at the secondary level. This approach emphasizes the complex processes involved in the communication of possession events. [Malay culture, spirit possession, communication]
TL;DR: The results indicate that the ASPA or glass ionomer cement method is effective, and it has some distinct advantages over existing methods of treatment of these cavities.
Abstract: This study evaluated the usefulness of the alumino-silicate polyacrylate (ASPA) or glass ionomer cement in the treatment of hypersensitive cervical abrasion cavities. Various methods of treatment of hypersensitive cervical abrasion cavities have been described, and all these methods have their disadvantages. The ASPA cement was used to treat non-carious hypersensitive cervical abrasion cavities in 189 teeth from fifty-eight adult patients. The patients were followed-up for periods ranging from 6-15 months. Of the 189 treated teeth, the ASPA restoration was intact in 163 or 86.2%. Seventeen teeth or 9.0% had partial loss of the restorations and nine or 4.8% had complete loss of restorations. With regard to symptoms, 176 or 93.1% of the treated teeth were no longer sensitive to stimuli from the oral cavity following placement of the ASPA restoration. Of the fifty-eight patients, fifty-two or 89.7% were completely relieved of all symptoms. Of the remaining teeth eleven or 5.8% reported a reduction in the severity of the symptoms. Only one patient, with both restorations lost, reported no improvement. No case of pulpal death was recorded, and there was no evidence of caries at the margin of any of the restorations. The results indicate that the method is effective, and it has some distinct advantages over existing methods of treatment of these cavities.
TL;DR: Present data indicate that these genes are not linked, and the frequencies of the three glucose phosphate isomerase genotypes are in accord with Hardy-Weinberg expectations.
Abstract: Glucose phosphate isomerase (EC 5319) and phosphoglucomutase (EC 2751) were found to be polymorphic in a laboratory colony of Aedes albopictus The glucose phosphate isomerase locus is represented by two alleles resulting in three genotypes, while the phosphoglucomutase locus is represented by at least five alleles giving rise to a total of 15 genotypes The inheritance of these two enzymes is of the Mendelian type with codominant alleles Present data indicate that these genes are not linkedOf 105 mosquitoes analysed for these two gene-enzyme systems, the frequencies for glucose phosphate isomerase alleles are Gpi (S)=068 and Gpi (F)=032, while the frequencies for phosphoglucomutase alleles are Pgm (A)=016, Pgm (B)=011, Pgm (C)=019, Pgm (D)=030 and Pgm (F)= 024 The frequencies of the three glucose phosphate isomerase genotypes are in accord with Hardy-Weinberg expectations (X 1 (2) =274) Similarly, the frequencies of the 15 phosphoglucomutase genotypes probably do not differ significantly from Hardy-Weinberg expectations (X 10 (2) = 1845)
TL;DR: In this article, the formation constants of uracil, uridine and thymidine with [Pd(dien)(OH2)]2+ and these ligands were determined potentiometrically at I = 0.5 mol dm−3 KNO3 and 25°C.
TL;DR: The structure of 3α, 9β, 13α-trihydroxy-1β, 8β-trinervita-11(12), 15(17)-diene was established by X-ray crystallography.
TL;DR: A seroepidemiological study was carried out on Orang Asli children who lead a semi-nomadic life in the deep jungles of Ulu Kelantan, Malaysia, and there was a positive correlation between antibody and spleen rates up to the age of 9 years.
Abstract: A seroepidemiological study was carried out on Orang Asli (Aborigines) children who lead a semi-nomadic life in the deep jungles of Ulu Kelantan, Malaysia. Out of a total of about 190 children below 14 years, 143 were studied. Blood was collected from finger pricks on standard "strip type" filter papers for indirect fluorescent antibody (IFA) tests with Plasmodium falciparum antigen. A positive reaction at 1:10 dilution in infants and young children was considered positive and the reasons are given. The P. falciparum antibody prevalence rate was 84.6% compared to 81.8% spleen and 43.4% parasite rates. Both P. Falciparum and P. vivax were present in children. The age-specific patterns of antibody, spleen and parasite rates were those of a hyperendemic community. There was a positive correlation between antibody and spleen rates up to the age of 9 years. In older children, the antibody rates increased while the spleen and the parasite rates dropped.
TL;DR: A syndrome of intracranial hemorrhage with gross prolongation of the prothrombin and partial thromboplastin times, with normal thrombin time, fibrinogen concentrations, and coagulation factor assays is described in four children with homozygous beta-thalassemia.
TL;DR: Analysis of the fatty acid composition of each of the leaf lipids revealed that, with the exception of steryl esters, all leaflipids have high content of polyunsaturated fatty acids.
Abstract: Lipids were extracted quantitatively from young cassava (Manihot esculenta Crantz) leaves with a chloroform-methanol mixture. Total lipids were purified by the Folch procedure and separated into non-polar lipid, glycolipid and phospholipid fractions by column chromatography. Lipids of each fraction were further subjected to thin layer chromatography and gas-liquid chromatography. Young cassava leaves were found to have low content of lipids (3.02%) of which 22.4, 25.1 and 48.2 were non-polar lipids, glycolipids and phospholipids, respectively. Pigments (11.5%), wax and hydrocarbons (1.2%), steryl esters (2.9%), methyl esters of fatty acids (2.0%), trigly-cerides (1.5%), fatty acids (2.1%), diglycerides (1.1%) and sterols (0.1%) constituted the leaf non-polar lipids. The leaf glycolipids were made up of esterified steryl glycosides (2.1%), monogalactosyl diglycerides (12.5%), steryl glycosides (1.1%), cerebrosides (4.2%) and digalactosyl diglycerides (5.2%). The leaf phospholipids were found to include cardiolipin (3.6%), phosphatidylglycerol (21.5%), phosphatidylethanolamine (16.4%), phosphatidylserine (0.7%), phosphatidylinositol (4.0%) and other unidentified phospholipids (2.5%). Phosphatidylcholine was present only in trace quantity. Analysis of the fatty acid composition of each of the leaf lipids revealed that, with the exception of steryl esters, all leaf lipids have high content of polyunsaturated fatty acids.